1. Field
Exemplary embodiments of the present invention relate to semiconductor design technology, and more particularly, to a nonvolatile memory device that can maintain stored data even when a power supply is interrupted.
2. Description of the Related Art
A nonvolatile memory device, such as a NAND type flash memory device, which is able to maintain stored data even when a power supply is interrupted, may increase in storage capacity.
As the level of integration for a memory cell increases with the increase in the storage capacity, a phenomenon such as a change in a threshold value due to the potential of a floating gate of an adjacent cell may occur. Such a change in a threshold value is referred to as a proximity effect.
The proximity effect changes the threshold value of a memory cell for writing data into the memory cell. The proximity effect is an obstacle when narrowing a threshold value distribution width and is regarded as one of factors that make it difficult to increase the storage capacity of a nonvolatile memory device.